Easmus foesholm



(No ModeL) R. PORSHOLM.

\ MOUNTING SCREW PROPELLERS- No. 315,136. Patented Apr. 7, 1885.

UNITED STATES PATENT OF ICE.

RASMUS FORSHOLM, OF NEW YORK, N. Y.

MOUNTING SCREW-PROPELLERS.

SEPECIPICATION forming part of Letters Patent No. 315,136, dated April'7, 1885.

(No model.)

To all whom it may concern.-

Be it known that I, 'RAsMUs FoRsHoLM, a citizen of Sweden, and aresidentof New York,

' in the county and State of New York, have however, leaking from theminto the boat.

The invention will be hereinafter described and claimed with referenceto the accompanying drawings, in which- Figure 1 represents alongitudinal vertical central section of the aft part of a boat with mypresent improvement applied to it. Fig. 2 is a detail similar section ona larger scale than Fig. 1, showing the means of attaching thepropeller-sleeve to the sternpost. Fig. 3 is a rear view of thestern-post, showing the face view of the bracket or plate by which theouter end of the propeller-sleeve is held, or as if seen in thedirection of the arrow in Fig. 2.

A is the stern-post; B, the keel; C, the ordinary locker at the stern ofthe boat; and D, the stern-seat, upon which a person is generally seatedin steering a boat. E is the first thwart in front of the stern-seat D.F is the rud- 7 der. G is the propeller. proper, and g thepropeller-shaft. The horizontal propeller-shaft g is provided on itsinner end with a small conical gear-wheel, H, which gears with a largerhorizontally arranged conical gear wheel, I, mounted upon the lower endof an upright shaft, J, at 'the upper end of which latter is attachedawinch or crank, j, or other suitable means by which to turn the shaft Jwith moderate velocity, and thereby to impart by means of the wheels I Ha faster velocity to the propeller G. The parts as thus far describedare old.

In order now to readily provide a boat with a screw-propeller and insurethe easy working of the shafts without liability of leaking, asaforesaid, I have provided the following devices: A flat bar or plate,a, securable above the keel of the boat by bolts or screws b, isprovided with a box or casing, c, for inclosing the gear-wheels I H, andwith a cen tral stud or projection, 11, in which the inner ends of theshafts J and 9 have their bearings, as shown in'Fig. 1. The box orcasing c is provided on top with a water-tight fitted cap or cover, 6.In rear of the casing c the plate a is provided with an upright lug, f,

"which may be arranged at a greateror less distance from the box c--forinstance, as where indicated by dotted lines at f and the object ofwhich is to insure the proper location of the propeller-shaft relativeto the gearing with its shaft J. The shaft g and the upright shaft J,instead of having their bearings in stuffing-boxes (to prevent theentrance of water, but at the same time causing a great deal of frictionto be overcome in the propulsion) are mounted in sleeves or tubes h 2',provided iuteriorly at their ends with bearings hc", for the respectiveshafts 9 J. The sleeves or tubes 13 h are secured water-tight in holesthrough the cover a, and the rear wall of the box 0, respectively, thesaid rear wall and aforesaid lug f being bored through at the same time,so as to be in axial line with each other and with the bearing, in d, ofthe inner end of the shaft 9. When the last-mentioned bearing is used,the inner bearing, h, may be dispensed with. For inserting the propellerin the boat it is only necessary to bore through the stern-post a holeof proper size to receive the aforesaidsleeve h, the outer end of which,projecting a little beyond the stern'post, is fitted water-tight in thelatter. This is done by means of a plate, K, (see Figs. 2 and 3,) whichis provided with a perforated boss, k, which surrounds the outer end ofthe sleeve h, a nipple or packing, L, of rubber or other suitablematerial, being inserted between the said boss and the tube hand clampedbetween the latter and the end surface of the stern by means of suitablescrews, Z, by which the plate K is secured in place. The propeller maybe arranged so as to project with its blades below the keel, as shown inthe drawings, or to end flush with or a little above the lower surfaceof the keel. In either case, for the sake of convenience, I form uponthe lower end of the plate K a horizontal lug, k, and attach to thelatter the lower pintle, m, for the 5 rudder F, while the upper pintle,n, may be moving in a lug attached to the stern-post directly, or may beattached to the stern-post,

. and a lug on the rudder working upon it.

For the sake of strength, Iarrange underneath the keel a brace, M, andsecure the rear end thereof to the lower end of the plate K, or its lug,and the forward end to the keel, as shown in the drawings. By thisconstruction, it is evident that the ends of the tubes M I being packedwater-tight, as aforesaid, no water can enter the boat through them, norfrom the box 0 with the water-tight packed cover e, but the water hasfree access between the shafts and their bearings in the ends of theaforesaid sleeves or tubes, thus acting as alubricator for the journalsand obviating the friction due to the use of st11ffingboxes..-I

It should be observed, however, that the upright sleeve or tube i shouldextend a little f above the water-line for the purpose of pre ventingthe water rising in the said tube around the upright shaft J fromoverflowing the said tube.

Y Having thus described my invention, I

0 claim as new and desire to secure by Letters Patent 1 The combinationof the propeller-shafts 9 J and their connecting gearing with aninclosing continuous water-tight casing, h Gi, projecting with its upperinner end above the waterline, and packed around itslower outer end tothe boat, substantially as set forth.

2. As a ready device for applying screwpropeller-shaft and protrudingthrough the said stern, of an eXteriorly-attachable stern plate, K,having a perforated boss, k, surrounding the outer end of the said tube,and a packing, L, interposed between the said 1 boss and tube,substantially as set forth.

I In testimony that I claim the foregoing as I myinvention I have signedmy name, in pres- 1 ence of two witnesses, this 22d day of April, 1884.

. RASMUS FORSHOLM.

R. W. NIATTHEWS,

i I Witnesses: i A. W. ALMQVIST.

propellers to boats, a fastening-plate, a, carboat and with a sleeve ortube, h, incasing the

